diffusion, osmosis, active transport Flashcards
what is diffusion?
the passive movement of molecules from an area of high concentration to an area of low concentration
what can travel using diffusion?
water, oxygen and carbon dioxide
factors that affect diffusion?
distance travelled, mass of the solute, temperature of the environment, solvent density
what is osmosis?
the movement of molecules through a partially permeable membrane from an area of low concentration to an area of high concentration
what can travel using osmosis?
only water
factors that affect osmosis?
water potential gradient
surface area
temperature
what is active transport?
the movement of a substance against the concentration gradient.
what is the concentration gradient?
high concentration -> low concentration
surface area affects?
increased surface area increases the rate of diffusion, osmosis and active transport. this is because there is more space for the molecules to move around freely and quickly
volume : surface area affects?
increased volume/ decreased surface area decreases the rate of diffusion, osmosis and active transport. this is because there is a greater volume that needs the substance being transported but a smaller entry point
distance affects?
a smaller distance increases the rate of diffusion, osmosis and active transport. this is because the particles do not have to travel too far
temperature affects?
higher temperatures increase the rate of diffusion, osmosis and active transport. this is because the heat increases the kinetic energy and therefore, the heat
concentration gradient affects?
large concentration gradient increases the rate of diffusion, osmosis and active transport. concentration drives the transportation of molecules.
what is water potential?
water potential is how likely it is for water molecules to diffuse out of or into solutions
water potential compared to concentration?
low water potential is high concentration.
high water potential is low concentration.
pure water?
pure water has the highest water potential possible because it has the most amount of water molecules and is the least concentrated.
plasmolyzed?
low water potential. when a cell is plasmolyzed, water has moved out of the cell into the solution around it
flaccid
normal water potential
turgid
high water potential. when a cell is turgid, the vacuole is swollen causing the cell membrane to press up against the cell wall
hypertonic
high solute concentration and low water concentration
isotonic
when two solutions have the same concentration of solutes across a semi-permeable membrane
hypotonic
low solute concentration and high water concentration
